The goal of NASA's Commercial Crew program, as it's called, is to taxi astronauts to and from the $150-billion International Space Station (ISS). Accomplishing that would close an increasingly expensive gap in the US' space-travel capabilities.

Williams is slated to fly aboard Boeing's second test flight to the ISS.

"Five years ago, this would have been like, 'No way, what are we doing asking commercial providers to be able to do this?'" Williams told Business Insider in June. "Now it feels like a natural progression for space travel."

Williams has flown inside three spaceships, served as commander of the International Space Station, lived in orbit for 322 days, and piloted 30 different types of aircraft for the Navy.

This extensive resume has come in handy over the past three years, as Williams has worked closely with Boeing and SpaceX. She and her colleagues have poked and prodded spacecraft mock-ups, tried on new spacesuits, fiddled with control panels, tested out simulators, and provided frank and sometimes critical feedback.

Here's why NASA needs Boeing and SpaceX, what Williams thinks of their new ships and suits, and how she's preparing to blast off into the uncharted territory of a new space race.

This story was updated with new information. It was originally published on June 24, 2018.

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Williams said she and the rest of the "Commercial Crew Cadre," as they're called — astronauts Doug Hurley, Eric Boe, and Bob Behnken — have worked "hand-in-hand" with Boeing and SpaceX since being assigned to the program by NASA in 2015.

NASA astronauts who will be the first to fly inside SpaceX's Crew Dragon. Left to right: Doug Hurley, Eric Boe, Bob Behnken, and Sunita Williams.SpaceX

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NASA announced on Friday that those four astronauts would be some of the first to fly crewed missions for Boeing and SpaceX, along with five others: John Cassada, Chris Ferguson, Victor Glover, Mike Hopkins, and Nicole Mann.

NASA started the Commercial Crew program to replace its space shuttles. The cost of shuttle launches was high: Each mission cost about $1.5 billion, including development costs, and 14 astronauts died. The 135th and final mission launched in July 2011.

So when NASA sent Williams to the International Space Station (ISS) in 2012, the agency had to buy her a seat on a Russian Soyuz spaceship. To this day, Soyuz is still the only spacecraft able to journey to and from the ISS.

Russia has used its monopoly to drive up Soyuz flight prices. In 2011, a round-trip ticket cost about $22 million; today, it costs NASA about $81 million to fly one astronaut.

In anticipation of this pickle, NASA started a competition to encourage companies to build their own spaceships. Boeing and SpaceX came out on top. "Competition is positive. It makes people do things a little smarter, potentially a little faster," Williams said.

Sierra Nevada's Dream Chaser spacecraft in an aerodynamic test as part of NASA's Commercial Crew program.NASA

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Boeing has earned about $4.8 billion in government contracts and awards for its work on the program since 2010, while SpaceX has earned about $3.1 billion. Boeing's CST-100 Starliner can carry seven people, which is as many as the space shuttle.

SpaceX's Crew Dragon can also seat up to seven space-flyers and last seven months at the space station.

An illustration of SpaceX's Crew Dragon, also known as Dragon 2 or Dragon V2, orbiting Earth. (The first Dragon was a cargo and supply ship not designed to carry people.)Kennedy Space Center/SpaceX via Flickr

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Williams' path into the seat of the CST-100 Starliner began in December 2006, when she made her first flight into orbit aboard space shuttle Discovery.

A portrait of NASA astronaut Sunita Williams in a bulky External Mobility Unit (EMU) spacesuit in September 2004.NASA

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She lived and worked aboard the International Space Station with two Russian cosmonauts, returning home on space shuttle Atlantis in April 2007.

The crew of the Expedition 15 space station crew. Left to right: NASA astronaut Sunita Williams; cosmonauts Fyodor Yurchikhin and Oleg Kotov.NASA

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Williams says her initial work on Commercial Crew was mostly PowerPoint presentations and discussions. Only in the past year and a half have astronauts started working with simulators and real hardware. "It's been hot and heavy in the last six months," she said.

Models of the spaceships that will launch astronauts are now nearing completion or undergoing testing.

The state of construction for Boeing's first CST-100 Starliner spaceship in March 2018.Boeing

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The controls are one huge difference Williams has noticed when comparing the Crew Dragon and Starliner to older spaceships. "The space shuttle was just littered with switches," she said. "You look at the cockpit, and there's switches everywhere."

"The way we described the space shuttle was that there were about 3,000 switches inside and there was no situation the astronauts couldn't make worse by touching the wrong button at the wrong time," Behnken said during NASA's announcement on Friday. "We're grateful that the next vehicle that we're going to fly on is going to be a little bit more automated."Pierre Ducharme/Reuters

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SpaceX's Crew Dragon and Boeing's Starliner simplify that labyrinth into a few glowing screens and buttons. "That just makes things easier, and makes things a little bit more changeable," Williams said. "Upgrades can happen a little bit easier, because it's software."

Physical switches are mostly absent in the new spacecraft, since their computers, sensors, and algorithms automate most tasks, especially tedious ones. But Williams says she and the crew felt Boeing and SpaceX's ships showed them too little on-screen information, at least initially — and told the companies as much.

"Automation can help us, but then you do have to watch out," Williams said. "We talked to the both partners about: How do I check this? I have a timeline in front of me — how do I know these things are happening? Where do I check? Where do I look? What's my confirming cue?"

"The big thing is you want to keep situational awareness. You don't want to be fat, dumb, and happy in there and something bad's going on," she said.

A spacesuit-clad person inside a mock-up of SpaceX's Crew Dragon looks up at the capsule's buttons, switches, and digital displays.SpaceX

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"Then when something is not going as planned, you know how to at least get the vehicle to a safe state," she added. "We can then talk to mission control in Hawthorne or here in Houston and say, 'Hey, what do we do next, and how do we handle this problem?'"

Williams says physical switches and buttons help ensure that astronauts can control a spacecraft in an emergency, such as loss of power. "It is a spacecraft, and there are some things that have to happen whether or not the electrons are flowing," she said.

These manual capabilities include "things that you really, really, really want to happen in case everything else dies," such as the deployment of parachutes for landing, Williams said.

Of course, every spaceship needs a spacesuit to protect astronauts if air starts leaking from the ship, or there's some other emergency. Williams said Boeing's and SpaceX's suits are similar to the Sokol suits, which Russia designed for its Soyuz capsule.

"Soyuz has seats that are molded to every body to help with the landing," she added. "Both of these companies have seats that keep that in mind."

"They're both different, and they're both better than suits that we've had in the past," Williams said. "It's gonna be fun to put a new spacesuit on."

Williams tests mock-ups of SpaceX's Crew Dragon spaceship and spacesuit in April 2018.SpaceX

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Getting into and out of each spacecraft's 3-foot-by-3-foot door isn't easy. "You climb in the door, you can't just walk in," Williams said. "The door is small because you don't want a humongous door that goes out to space." (The bigger the opening, the greater the risk of leaks and other problems.)

Though SpaceX's and Boeing's spaceships are roomier than a Soyuz, it's still pretty cramped. "You sort of feel like you're crawling around," Williams said. "It will feel like there's enough space when we get up into space. It helps when you can float and move away from things."

Each SpaceX Crew Dragon capsule will have four windows and seats made of high-grade carbon-fiber composites.
SpaceX

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The seat designs aren't finalized, so Williams has yet to see how comfortable they will be. "I haven't seen any leather seats yet," she said, joking. "You're going to be sitting on it or strapped into it; the thing it has to do is provide you protection."

The interior of SpaceX's Crew Dragon capsule showing seats for five astronauts, though the craft can support up to seven.SpaceX/Flickr (public domain)

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As for a bathroom? "There's limited amount of toilet-type stuff in there. There's a way to go for both companies, but it's not the best," she said.

Astronauts train inside a mock-up of Boeing's CST-100 Starliner spaceship. Three people — Boe, Ferguson, and Mann — will fly its first test mission.Boeing

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"The best thing is probably waiting till you get to the space station," Williams added.

NASA astronaut Sunita Williams smiles in her spacesuit in January 2011 while training for spaceflight.NASA

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The Commercial Crew program will launch uncrewed ships first, one per spacecraft, then follow up with two crewed flights each to the International Space Station.

"We've gotten into the cockpit in both spacecraft. We've run through parts of the profile, from launch to rendezvous docking, un-docking, and [atmospheric] entry. But everything's not been tied up, not quite yet," Williams said. She didn't say which company's spaceship is her favorite.

SpaceX's Crew Dragon spaceship undergoes testing for electromagnetic interference in a special chamber.SpaceX

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Crewed launch dates may slip deep into 2019. Williams says it will take about a year from now to complete mission training. Also, Boeing discovered a fuel leak with Starliner — the system Williams is to fly — which delayed its first crewed flight as a result.

An illustration of SpaceX's Crew Dragon spaceship docking with the International Space Station.SpaceX

SpaceX is aiming to do its uncrewed flight in November and Boeing in December. If successful, SpaceX may launch its first crew in February 2018 and Boeing in mid-2019. A second crewed flight will follow to fully certify each system.

An illustration of Boeing's CST-100 Starliner docking tot he International Space Station.Boeing

NASA originally wanted crewed launches to happen by 2017, but delays snowballed due to the agency's stringent safety concerns. It wants Boeing and SpaceX's spacecraft to have less than a 1-in-200 chance of killing a crew in an accident — three times less than the space shuttle.

"There will be what's called flight readiness reviews for all of these flights, and people will look at the risks," Williams said. "There'll be some explaining to do if there's any outstanding risk that hasn't been at least discussed and looked at and weighed."

Engineers test a zip line that may help NASA's Commercial Crew astronauts escape from a launchpad in an emergency.NASA/Leif Heimbold

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Williams and her colleagues are clear-eyed about the risk they're taking. In fact, two of them — Behnken and Hurley — were on the runway waiting for space shuttle Columbia's landing when they heard it had broken apart during atmospheric reentry.

A portrait of NASA's STS-107 mission crew members, who died in the space shuttle Columbia disaster on February 1, 2003.NASA

"Spaceflight is inherently dangerous. Something that we've never thought of could potentially happen," Williams said.

"This is our profession and this is what we're supposed to do. I think everybody will be up to the challenge and ready to go when the spacecraft are ready," she said. "Everybody believes, or they wouldn't be here, that what we're doing is for a bigger purpose."

Sunita Williams positions a communications headset during training in September 2011.NASA

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NASA has a little more than a year to certify either spaceship system, or it risks temporarily losing access to the space station. There are enough Soyuz flights to last NASA through the fall of 2019, but Russia wants three years of notice to prepare new missions.

NASA is building its own rocket and spacecraft, called Space Launch System, but that program won't fly its first astronauts until June 2022 at the earliest.

Overall, Williams said the International Space Station program is a model for "working with people that you weren't necessarily really friends with at one point in time." She added: "Russian cosmonauts are itching to fly on these spacecraft as well, and those are the ultimate signs of trust: We go jump in a Soyuz, we trust these guys to do the right thing, and they trust us as well."

"We're trusting these companies to do the right thing as well," she said. "All that collaboration, all that sharing of technology and information, and understanding each other along the way, I think those are hugely important and it's going to help us continue to explore."

Williams waves after her Aug. 3, 2018 selection to fly on the second crewed mission of CST-100 Starliner, a spaceship that Boeing designed and built for NASA.David J. Phillip/AP

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Williams said she's met with Elon Musk multiple times and discussed his hopes and dreams. "I'm hoping along the same lines that he is, that all of this type of stuff opens spaceflight to many, many, many more people," she said. "I feel like it's almost on the verge, like when aircraft went commercial."

"I think he understands that this program needs to be successful so that people all around the world would be happy to get in one of his spacecraft," Williams said of Musk. "The technology is there. It's time, and I'm hoping in our lifetime we see more people go to space and eventually somebody to Mars."

Correction: A previous version of this story cited target launch dates for Boeing and SpaceX's demonstration missions that differ from NASA's Commercial Crew website. Those dates have been clarified and updated with the best information available as of August 3, 2018.